Reality check: The NX MUST be successful.

[JEMC]

I agree that NX will mark the future of Nintendo because if it fails, the company will go through big changes: Iwata will leave (either voluntarily or forced by the shareholders), and right after him most of the current directives will also leave, including Miyamoto whose vision of Nintendo has been a key factor on how and why the last consoles from Nintendo have been the way they have been.

Because of that, a post NX failure Nintendo would be a different company. And I can see that new Ninendo going through three possible ways:

1-One last try. With a more simpler and direct approach,a  powerful console/platform and little-to-no gimmicks, they'll probably try to recapture the gamer market with a system on par with what their rivals will show.

2-Become a third party or a privileged second party. I can see Nintendo going both ways, to be honest, because if you don't develop for your own hardware, the best option is to develop for every other platform, but that demands bigger teams and a lot more testing to develop and launch quality products. Because of that and given Nintendo's reluctance to grow during the last console cycles, I could see them trying to get away with a special relationship with either MSoft or Sony (my bet is they would try it first with Sony since they sell well on every market) and launch their games only on one console. Of course, besides that, they will expand their mobile division.

3-Go full mobile. Quite simple, they'll stop developing console hardware and software and focus on their new mobile strategy.